Abstract. We are requesting an administrative supplement to expand participant recruitment and testing to the VA Northern California Healthcare System (VANCHCS) in Martinez. The supplement would reduce five potential risks to the long-term scientific impact of second generation California Cognitive Assessment Battery (CCAB-2) tests: ? Recruitment. Participant recruitment has been compromised by the establishment of a California-funded Alzheimer?s Disease Research Center at our original recruitment site. Expanding recruitment and testing to the VANCHCS will resolve this problem and increase participant diversity: there are more than 32,000 eligible older participants within the VANCHCS catchment who meet study inclusion criteria. ? Milestone completion. Our research plan calls for nearly 5,000 assessments over three years, with nearly 2,300 assessments planned in Phase II, year 1. This would require 9.1 assessments per day during year 1, i.e. approximately 20 hours of testing. The assistance of trained VA staff and the established VANCHCS? infrastructure will assist us in meeting these testing challenges. ? CCAB-2 compatibility with hospital data security protocols. In the original application, CCAB-2 testing was limited to NBS offices. The supplement will support the software development and testing needed to ensure that CCAB-2 tests function within secure healthcare IT networks with extensive data protection safeguards and HIPAA-compliant protocols. ? CCAB-2 usability and robustness. In the original application, CCAB-2 test administration was limited to NBS personnel. This administrative supplement will enable extensive field testing by VA scientists and clinicians to ensure CCAB-2 robustness and usability prior to commercial launch. ? Disseminating results. The extensive testing demands in the original application would limit NBS scientific outreach. The supplement will support VA scientists in publicizing CCAB-2 capabilities at conferences, Alzheimer?s Disease Centers, grand rounds, research labs, department colloquia, and in peer-reviewed publications.